JP4226184B2 - Information recording medium discriminating apparatus and information recording medium discriminating method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention belongs to the technical field of an information recording medium discriminating apparatus and an information recording medium discriminating method, and more specifically, an information recording medium discriminating apparatus for discriminating the type of information recording medium on which information is recorded or reproduced optically. And belongs to the technical field of the information recording medium discrimination method.
[0002]
[Prior art]
In recent years, information reproducing apparatuses with excellent so-called compatibility that can reproduce information recorded on a plurality of different types of optical discs with one information reproducing apparatus have become common.
[0003]
On the other hand, when reproducing information from the optical disc, generally, so-called focus servo control or tracking servo control is executed in order to make the light beam focusing position for reproduction coincide with the position of the information recording surface of the optical disc. However, it is necessary to perform the reproduction.
[0004]
Here, in various conventional optical discs, the gain characteristics and the equalizer characteristics that should be set in each servo control described above are usually different from each other due to structural differences.
[0005]
Therefore, in reproducing information recorded on each information reproducing apparatus, each characteristic (such as the equalizer characteristic or gain characteristic) in the information reproducing apparatus is optimized after being optimized according to the type of each optical disk. In order to do this, before executing the reproduction, the type of the optical disk currently loaded in the information reproducing apparatus is determined, and the gain characteristics are determined based on the determination result. Etc. need to be optimized.
[0006]
For this reason, conventionally, various types discrimination methods using a light beam for recording or reproducing on an optical disc have been proposed.
[0007]
[Problems to be solved by the invention]
However, a so-called CD-R (Compact Disc-Recordable), which can be recorded only once, which is being generalized recently, can be discriminated from other optical discs using any conventional type discriminating method. There was a problem that could not.
[0008]
This is because, with respect to a light beam used in a conventional information reproducing apparatus for CD (Compact Disc), the reflection characteristics and recording format of the CD-R with respect to the light beam are almost the same as those of other CDs. Therefore, the CD-R and the CD cannot be distinguished from each other using any of the conventional type discrimination methods using the light beam.
[0009]
On the other hand, in recent years, it has become necessary to reproduce the CD-R at a high speed. In this case, it is necessary to rotate the CD-R at a high speed. In the case of accurately reproducing information from the CD-R rotating at high speed, the gain characteristic or the equalizer characteristic, etc., which are allowed even with the same setting as the CD at the time of low-speed rotation, are further improved. It is necessary to set the value optimized only for the CD-R. For this reason, the need to distinguish the CD-R from other optical discs before reproducing information is further increased.
[0010]
Therefore, the present invention has been made in view of the above-described demands, and the problem thereof is information recording that can optically accurately determine the types of a plurality of types of information recording media including a CD-R. The object is to provide a medium discriminating apparatus and an information recording medium discriminating method.
[0011]
[Means for Solving the Problems]
  In order to solve the above problem, the invention according to claim 1 is characterized in that the first laser diode and the second laser diode that emit a plurality of light beams having different wavelengths from each other, and the emitted means Using light receiving means such as a pickup that receives reflected light from the information recording medium of each light beam and outputs a received light signal corresponding to the received reflected light, respectively, and using each of the output received light signals,eachA tracking error signal group including a tracking error signal corresponding to each of the light beams, or R corresponding to each of the light beams.FRF signal group includingNoisySlipperyon the other handGenerating means such as a pickup for generating a signal group, and any one of the above corresponding to each of the light beamson the other handOnly based on the amplitude ratio of signals included inCD-R, CD-RW, DVD (S), DVD (D), DVD-R, or DVD-RWOf the information recording mediumConcernedDiscriminating means such as a servo IC (Integrated Circuit) for discriminating types.
[0025]
  To solve the above problems, the claims7In the invention described in (1), an emission step of emitting a plurality of light beams having different wavelengths from each other, reflected light from the information recording medium of each of the emitted light beams, respectively, and the received reflected light respectively Using a light receiving process for outputting a corresponding light receiving signal and each of the outputted light receiving signals,eachA tracking error signal group including a tracking error signal corresponding to each of the light beams, or an RF signal group including an RF signal corresponding to each of the light beams,NoisySlipperyon the other handA generating step for generating a signal group of any one of the above, and each of the light beams corresponding to each of the light beamson the other handOnly based on the amplitude ratio of signals included inCD-R, CD-RW, DVD (S), DVD (D), DVD-R, or DVD-RWDiscriminating step for discriminating the type of the information recording medium.
[0029]
DETAILED DESCRIPTION OF THE INVENTION
Next, a preferred embodiment of the present invention will be described with reference to FIGS.
[0030]
The embodiment described below is an embodiment in which the present invention is applied to an optical disc type determination process in an information reproducing apparatus capable of reproducing information recorded on a plurality of types of optical discs.
[0031]
FIG. 1 is a diagram for explaining the principle of the present invention, FIG. 2 is a block diagram showing a schematic configuration of an information reproducing apparatus according to the embodiment, and FIG. 3 is a flowchart showing a type determination process according to the embodiment. FIG. 4 is a timing chart showing the type determination process according to the embodiment.
[0032]
(I)Principle of the present invention
First, before describing specific embodiments, the principle of the present invention will be described with reference to FIG.
[0033]
Currently, as an information recording medium on which information is optically reproduced in the same manner as a CD, CD-R, CD-RW (CD-ReWritable), DVD (S) (due to differences in recording capacity or recording format) There are a DVD-Single layer, a DVD (D) (DVD-Dual layer), a DVD-R (DVD-Recordable), a DVD-RW (DVD-Re-recordable), and the like.
[0034]
At this time, the CD-R is a recording / reproducing optical disc that can be written only once and has a recording capacity almost the same as that of a CD, and the CD-RW can be recorded or reproduced a plurality of times and recorded almost the same as a CD. A recording / reproducing optical disk having a capacity, DVD (S) is a reproduction-only optical disk having a recording capacity several times higher than that of CD, and DVD (D) is more than a CD having a two-layer information recording surface. This is a read-only optical disk with a recording capacity increased by a dozen times. A DVD-R is a recording / reproduction optical disk that can be written only once and has almost the same recording capacity as the DVD (S). Is a recording / reproducing optical disc having the same recording capacity as that of the DVD (S).
[0035]
Furthermore, among these, DVD (D), DVD (S), DVD-R, and DVD-RW can be recorded or reproduced using a light beam having a wavelength of 650 nanometers, for example. , CD-R, CD, and CD-RW can be recorded or reproduced using a light beam having a wavelength longer than 780 nanometers.
[0036]
Here, in each optical disk, the above-described reflection film (reflection film for reflecting the irradiated light beam) is different due to the difference in the material and the difference in the laminated structure of the optical disk itself. There is a difference in reflectivity for each light beam.
[0037]
On the other hand, in the information reproducing apparatus capable of reproducing all the information recorded on each of the optical discs described above, the laser diode that emits the light beam having the wavelength of 650 nm and the light beam having the wavelength of 780 nm are emitted. Both are equipped with a laser diode.
[0038]
Therefore, in the present invention, when discriminating the type of the optical disc loaded in the information reproducing apparatus at the time of information reproduction, the above-mentioned two types of light beams are separately irradiated to the loaded optical disc. The ratio of the amplitudes of two types of light reception signals (specifically, light reception signals such as so-called focus error signal, tracking error signal or RF (Radio Frequency) signal) obtained by receiving the reflected light, respectively, is calculated. Based on the amplitude ratio, the type of the loaded optical disk is determined.
[0039]
More specifically, using the fact that the amplitude ratio shows the distribution as shown in FIG. 1 according to the type of the optical disc, a plurality of thresholds for the amplitude ratio as shown by reference signs A to D in FIG. The type of the loaded optical disk is discriminated on the basis of how the amplitude ratio obtained corresponding to the loaded optical disk is related to each threshold value, and subsequent reproduction is performed.
[0040]
In the present invention, the type of the optical disk is not determined based on the difference in reflectance with respect to any one of the light beams, but the type is determined based on the amplitude ratio of the received light signals corresponding to the two types of light beams. What is determined is that the optical discs have different reflectances even if they are the same type of optical discs, and the information reproducing apparatus also has so-called individual differences in the light receiving characteristics of the respective light beams. In some cases, the type is discriminated based on the amplitude ratio in order to compensate for these variations or individual differences and to discriminate the type stably.
[0041]
(II)Embodiment
Next, an embodiment of the present invention will be specifically described with reference to FIGS.
[0042]
First, a schematic configuration and operation of the information reproducing apparatus according to the embodiment will be described with reference to FIG.
[0043]
As shown in FIG. 2, an information reproducing apparatus S for reproducing information recorded on an optical disk 1 (any one of the seven types of optical disks described above) includes a spindle motor 2 and light receiving means. Pickup 3, carriage 4, rotating shaft 5, carriage motor 6, decoder 7, memory 8, servo IC 9 as discrimination means and presence / absence discrimination means, I / F (Inter Face) controller 10, And a control microcomputer 11.
[0044]
Next, an outline operation will be described.
[0045]
First, a laser diode (LASER Diode; hereinafter referred to as a second laser diode) 3B that emits a light beam having a wavelength of 650 nanometers and a laser diode that emits a light beam having a wavelength of 780 nanometers. (Hereinafter referred to as the first laser diode.) The pickup 3 provided with 3A is attached to the optical disk 1 rotated at a predetermined rotational speed set in advance by a spindle motor 2 driven by a spindle drive signal Ssd described later. On the other hand, a light beam B for information reproduction is irradiated and the reflected light is received to generate a detection signal Spu corresponding to the information to be reproduced and output it to the decoder 7.
[0046]
At this time, which of the two types of wavelengths is emitted as the light beam B is determined based on the type of the optical disc 1 determined by the type determination process described later.
[0047]
Further, the light beam B is condensed on an information recording surface in the optical disc 1 by an objective lens (not shown) in the pickup 3 to form a light spot on the information recording surface.
[0048]
Then, the deviation in the direction perpendicular to the information recording surface and the horizontal position between the condensing position of the light beam B and the position of the information track (information track on which information is recorded or reproduced) formed on the information recording surface. Such a deviation in direction is caused by the objective lens being moved in the vertical direction or the horizontal direction by an actuator (not shown) driven by a pickup servo signal Spd described later (an actuator that supports and moves the objective lens). Information is reproduced while being compensated (that is, while tracking servo control and focus servo control are being performed).
[0049]
In the tracking servo control in the radial direction of the optical disk 1, if it becomes necessary to move the condensing position beyond the movement limit of the objective lens in the radial direction, the carriage 4 that supports the pickup 3. Tracking servo control is continued by moving while supporting the pickup 3 in the radial direction (left and right direction in FIG. 2).
[0050]
At this time, the movement of the carriage 4 is meshed with the screw on the rotating shaft 5 by the rotation of the rotating shaft 5 that is threaded by a carriage motor 6 driven by a motor driving signal Smd described later. This is realized by moving the carriage 4 on which the partial nut is formed in a direction parallel to the central axis of the rotating shaft 5.
[0051]
The switching control between the first laser diode 3A and the second laser diode 3B is executed under the control of the servo IC 9 using the switching control signal included in the pickup servo signal Spd.
[0052]
Next, the decoder 7 sends and receives the control signal Scd to and from the control microcomputer 11 and sends and receives necessary information to and from the memory 8 as the memory signal Sm, and is recorded on the optical disc 1 from the detection signal Spu. A reproduction signal Sdc corresponding to the recorded information is extracted and output to the I / F controller 10, and the detection signal Spu has a light beam B condensing position and the information track position in a direction perpendicular to the information recording surface. The focus error signal indicating deviation and the tracking error signal indicating deviation in a direction parallel to the information recording surface are extracted, and an error signal Ses including these is generated and output to the servo IC 9.
[0053]
As a result, the I / F controller 10 performs a preset interface process on the reproduction signal Sdc while exchanging the control signal Scc with the control microcomputer 11, and information recorded on the optical disc 1. Is generated and output to an external personal computer or the like.
[0054]
On the other hand, the servo IC 9 to which the error signal Ses is input exchanges the control signal Scs with the control microcomputer 11 and based on the focus error signal and the tracking error signal included in the error signal Ses. The pickup servo signal Spd for driving the actuator in the pickup 3 is generated and output to the pickup 3, and the spindle drive signal Ssd for controlling the rotation of the spindle motor 2 is generated to generate the spindle motor. Output to 2.
[0055]
In addition, the servo IC 9 generates the motor drive signal Smd and outputs it to the carriage motor 6 in order to move the carriage 4 in the radial direction of the optical disk 1 based on the tracking error signal.
[0056]
Further, the servo IC 9 controls turning on / off of the first laser diode 3A and turning on / off of the second laser diode 3B by using the switching control signal in a type determination process described later.
[0057]
Here, the series of operations described above are operations when information recorded on the optical disc 1 is reproduced. Before the reproduction operation is started, the type determination process of the optical disc 1 according to the present invention, which will be described later, is performed. Based on the result, the setting of the gain characteristic or the equalizer characteristic in the servo IC 9 is executed. Note that the focus error signal described above is used in the type determination process as described later.
[0058]
Next, the type determination process according to the embodiment will be described with reference to FIGS. 3 and 4. Note that the type determination process described below is a process mainly executed in the servo IC 9.
[0059]
In the type discrimination process before the start of information reproduction, first, the first laser diode 3A that emits the light beam B having a wavelength of 780 nm is turned on (step S1), and the reflected light from the optical disk 1 of the light beam B is reflected. Based on this, a so-called S-shaped signal included in the focus error signal is acquired (step S2).
[0060]
Then, it is determined whether or not an S-shaped signal is actually acquired (step S3). If it cannot be acquired (step S3; NO), it is determined that the optical disc 1 is not actually loaded in the information reproducing apparatus S. Then, a preset error process is performed (step S4), and the process is terminated.
[0061]
Here, the light beam B having a wavelength of 780 nanometers is used in the determination of whether or not the optical disk 1 is loaded. The light beam having a wavelength of 650 nanometers is hardly reflected on the CD-R as shown in FIG. Therefore, when the optical disk 1 loaded is a CD-R, if the presence / absence of the loading itself is determined using a light beam having a wavelength of 650 nm, the CD-R is actually loaded. This is because it may be determined that the battery is not loaded (step S3; NO).
[0062]
On the other hand, when the S-shaped signal can be acquired in the determination in step S3 (step S3; YES), the amplitude value of the acquired S-shaped signal is temporarily stored in a memory (not shown) in the servo IC 9 as the value A. The first laser diode 3A that is turned on is turned off (step S5), and then the second laser diode 3B that emits the light beam B having a wavelength of 650 nanometers is turned on (step S6).
[0063]
As in the case of step S2, an S-shaped signal is extracted from the obtained focus error signal, and the amplitude value of the acquired S-shaped signal is temporarily stored in the memory in the servo IC 9 as a value B. (Step S7) The second laser diode 3B that is turned on is turned off (Step S8).
[0064]
At this time, if the loaded optical disc 1 is, for example, the DVD (D), the focus drive signal (in the pickup 3) shown in the lower part of FIG. The focus error signal shown in the upper part of FIG. 4A is obtained along with the change in the focus drive signal for driving the objective lens in the direction perpendicular to the optical disc 1, and the corresponding value B is the value A. It will be obtained as a value of about twice.
[0065]
On the other hand, when the loaded optical disk 1 is, for example, the above-mentioned CD-R, the focus shown in the upper part of FIG. 4B is changed in the process along with the change of the focus drive signal shown in the lower part of FIG. An error signal is obtained, and the corresponding value B is obtained as a value smaller than the value A.
[0066]
When the amplitude value B corresponding to the light beam having a wavelength of 650 nanometers and the amplitude value A corresponding to the light beam having a wavelength of 780 nanometers are obtained for the optical disc 1 loaded by the series of processes described above, The type of the optical disc 1 is determined based on the amplitude ratio (specifically, the amplitude ratio indicated by B / A) (step S9).
[0067]
Specifically, regarding the processing in step S9, when the amplitude ratio is equal to or smaller than the threshold value D shown in FIG. 1, it is determined that the loaded optical disk 1 is a CD-R, and the amplitude ratio is larger than the threshold value D. When it is less than the threshold value C, it is determined that the loaded optical disk 1 is a DVD (D). When the amplitude ratio is greater than the threshold value C and less than the threshold value B, the loaded optical disk 1 is CD or CD−. When the amplitude ratio is greater than the threshold value B and less than the threshold value A, it is determined that the loaded optical disc 1 is DVD (S) or DVD-R, and the amplitude ratio is greater than the threshold value A. When it is larger, it is determined that the loaded optical disk 1 is a DVD-RW.
[0068]
If the type is determined, the gain characteristics and the equalizer characteristics are set in the servo IC 9 according to the determination result (step S10), and the information to be reproduced is reproduced (step S11). Exit.
[0069]
In addition, when the type can be specifically specified in the determination of step S9 (when the optical disc 1 is the above-mentioned CD-R, DVD (D), or DVD-RW), the type specified in step S10, respectively. Each characteristic is set so as to be optimized, but the type cannot be specifically specified in the determination in step S9 (when the optical disc 1 is determined to be a CD or a CD-RW) (If it is determined to be DVD (S) or DVD-R), in practice, after one type is specified using another method, the steps after step S10 are performed so as to correspond to the specified type. Processing is executed.
[0070]
At this time, specifically, as another method, for example, as a method of discriminating whether the optical disc 1 is a CD or a CD-RW, any one of the light beams using the difference in reflectance is used. Can be distinguished from CD-RW by comparing the absolute values of the reflected light.
[0071]
Further, as a method for determining whether the optical disk 1 is a DVD (S) or a DVD-R, for example, management information (management information describing the type of the optical disk) recorded in advance on each optical disk is used. By reading, DVD (S) and DVD-R can be distinguished.
[0072]
  As described above, in the information reproduction process involving the type determination process of the embodiment, the optical disk 1 is based on the ratio between the amplitudes of two S-shaped signals obtained by irradiating the optical disk 1 with two types of light beams. Therefore, the type can be discriminated optically simply and accurately.
Therefore, the type of the light beam used for recording or reproducing information with respect to the optical disc 1 can also be discriminated, and the configuration as the information reproducing apparatus can be simplified.
[0073]
Further, since it is possible to determine whether the optical disc 1 is a CD-R or another information recording medium excluding the CD-R, it is possible to optically determine that the optical disc 1 is a CD-R that has been impossible until now. Can be done.
[0074]
Furthermore, since the type of the optical disc 1 is determined based on the comparison between the preset thresholds A to D and the amplitude ratio, the type can be determined more reliably and easily optically.
[0075]
Furthermore, since the obtained light beam B having a wavelength of 780 nanometers is also used to determine whether or not the optical disc 1 is loaded prior to discriminating the type of the optical disc 1, the time required to start playback on the optical disc 1 is shortened. can do.
[0076]
In the above-described embodiment, the case where the type determination process is performed using the light beam B having two types of wavelengths has been described. However, the wavelength of the light beam B used for the type determination process is determined as a target of determination. As long as there are two types of wavelengths having different reflectivities with respect to the optical disk, it is not limited to the above-mentioned 650 nm and 780 nm.
[0077]
(III)Deformation
Next, modifications corresponding to the present invention will be described.
[0078]
First, as a first modification, in the above-described embodiment, the light beam B having a wavelength of 780 nanometers is first lit from the first laser diode 3A for the purpose of determining whether or not the optical disk 1 is loaded. If the determination of the presence / absence of the loading is performed by another method, the second laser diode 3B can be turned on first and the amplitude value B can be acquired first.
[0079]
Further, as a second modification, in the above-described embodiment, the type is determined using a light beam having a wavelength of 780 nanometers and a light beam having a wavelength of 650 nanometers. In addition, the wavelength is 770 nanometers. The amplitude value is calculated using the first light beam in the range of 795 nanometers or less and the second light beam having a wavelength in the range of 630 nanometers or more and 655 nanometers or less, and based on the ratio It can also be configured to determine the type.
[0080]
In this case, since the type of the light beam used for reproducing information on the optical disc 1 can also be discriminated, the configuration of the information reproducing apparatus itself can be simplified.
[0081]
Further, as a third variation, not only two types of light beams but also three or more types of light beams are sequentially used to obtain the corresponding amplitude values of the S-shaped signal, and the ratio of two of them is compared. It is also possible to discriminate optical discs other than the seven types described above by calculating and comparing with a predetermined threshold value.
[0082]
Furthermore, as a fourth modification, in the case of the third modification, if the light beam used for reproduction after type discrimination is finally used in the type discrimination, the laser diode is not switched as it is. It is possible to shift to the reproduction.
[0083]
At this time, the configuration of the information reproducing apparatus S of the embodiment will be described more specifically as the fourth modification. For example, the first laser diode 3A is turned on to determine whether or not the optical disk 1 is loaded. Later, when the first laser diode 3A and the second laser diode 3B are turned on once (the order does not matter) to perform the type discrimination process, in this case, the first laser diode for discriminating the presence or absence of the optical disc. At the stage of lighting of 3A, the loaded optical disc 1 is one of the above-mentioned CD, CD-R or CD-RW (hereinafter referred to as CD), or DVD (D), DVD (S). , DVD-R or DVD-RW (hereinafter referred to as DVD) can be discriminated between the two.
[0084]
That is, as a signal obtained when the optical beam is irradiated with the light beam B having a wavelength of 780 nanometers, in addition to the S-shaped signal obtained by reflecting the light beam B by the reflective film of each optical disc, There is what is called a so-called pseudo-S signal obtained by reflecting the light beam B by the protective layer of each optical disk. Until the original S-signal is obtained after this pseudo-S signal is obtained. This time varies depending on the distance between the protective film and the reflective film. Since this distance differs twice between the CDs (1.2 mm) and the DVDs (0.6 mm), reproduction is performed at the stage of lighting of the first laser diode 3A by detecting the time. The laser diode to be used can be specified (if the loaded optical disk 1 is a CD, the first laser diode 3A is used for reproduction, and if the optical disk 1 is a DVD, the second laser is used for reproduction. (The diode 3B will be used.)
Therefore, with regard to the order in which the laser diodes for type discrimination processing are turned on, if the laser diode used for reproduction after the discrimination processing is turned on later, actual reproduction can be started without switching the laser diode as it is. is there.
[0085]
In the specific description of the fourth modification described above, the case where the laser diode is turned on for convenience three times has been described, but in addition to this, the type of the laser diode used after the type determination process at a stage before the type determination process is determined. If it is discriminated (for example, it can be discriminated by the physical shape of the optical disc 1 itself, or by specifying the type of the optical disc 1 used by the user), the laser diode to be used after that is selected. By turning on the light last in the type determination process, the process after the type determination process can be performed as it is without performing the above switching.
[0086]
Further, as a fifth modification, in the above-described embodiment, the present invention is applied to the case where information recorded on the optical disc 1 is reproduced. However, in addition to this, necessary information for a recordable optical disc is provided. In the case of recording, the present invention can also be applied when discriminating the type of optical disc to be recorded as preprocessing.
[0087]
Further, as a sixth modification, a program corresponding to the type determination process shown in FIG. 3 is recorded on an information recording medium such as a flexible disk, a RAM (Random Access Memory) or a ROM (Read Only Memory), Can be configured to execute the type determination processing according to the embodiment in the information recording apparatus or the information reproducing apparatus.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating the principle of the present invention.
FIG. 2 is a block diagram showing a schematic configuration of the information reproducing apparatus according to the embodiment.
FIG. 3 is a flowchart showing a type determination process according to the embodiment.
FIG. 4 is a timing chart showing type discrimination processing according to the embodiment.
[Explanation of symbols]
1 ... Optical disc
2 ... Spindle motor
3 ... Pickup
3A ... 1st laser diode
3B ... Second laser diode
4 Carriage
5 ... Rotating shaft
6 Carriage motor
7 Decoder
8 ... Memory
9 ... Servo IC
10 ... I / F controller
11 ... Control microcomputer
S: Information reproducing apparatus
B ... Light beam
Ssd: Spindle drive signal
Spu ... Detection signal
Spd ... Pickup servo signal
Smd: Motor drive signal
Scd, Scc, Scs ... control signal
Sm: Memory signal
Sdc: Playback signal
Ses ... Error signal
Sout ... Output signal

Claims (8)

Emitting means for emitting a plurality of light beams having different wavelengths from each other;
A light receiving means for receiving reflected light from the information recording medium of each of the emitted light beams, and outputting light receiving signals respectively corresponding to the received reflected light;
A tracking error signal group including a tracking error signal corresponding to each of the light beams, or an RF signal group including an RF (Radio Frequency) signal corresponding to each of the light beams , using each of the output received light signals. a generating means for generating a noise Zureka one signal group,
-Out based only on the amplitude ratio between the signals included in said one signal group corresponding to each of said light beams respectively, CD-R (Compact Disc - Recordable), CD-RW (CD - ReWritable), DVD ( S) (DVD - Single layer) , DVD (D) (DVD - Dual layer), DVD-R (DVD - Recordable) or DVD-RW (DVD Re - recordable ) the type of the information recording medium is either Discriminating means for discriminating;
An information recording medium discriminating apparatus comprising: In the information recording medium discrimination device according to claim 1,
The emitting means emits a first light beam and a second light beam having different wavelengths from each other,
The light receiving means receives reflected light from the information recording medium of the first light beam and outputs a first light receiving signal, and receives reflected light from the information recording medium of the second light beam. Outputs a second received light signal,
The generating means, before Symbol tracking error signal a tracking error signal group corresponding to the tracking error signal and the second light receiving signal corresponding to the first light receiving signal, or the RF signal and the second light receiving corresponding to the first light receiving signal RF signal group including a RF signal corresponding to the signal to generate one of the signal groups Noi Zureka,
Further, the discriminating means discriminates the type of the information recording medium based only on the amplitude ratio of signals included in any one of the signal groups. In the information recording medium discriminating device according to claim 2,
The wavelength of the first light beam is in the range of 770 nm to 795 nm, and the wavelength of the second light beam is in the range of 630 nm to 655 nm. A characteristic information recording medium discrimination device. In the information recording medium discriminating device according to any one of claims 1 to 3,
The discriminating means determines the type of the information recording medium by comparing only the amplitude ratio with a threshold set in advance corresponding to the reflectance of each light beam in the information recording medium whose type is to be discriminated. An information recording medium discriminating apparatus characterized by discriminating. In the information recording medium discrimination device according to any one of claims 1 to 4,
An information recording medium discriminating apparatus further comprising presence / absence discriminating means for discriminating the presence / absence of the information recording medium based on any one of the outputted light reception signals prior to the type discrimination. In the information recording medium discriminating device according to any one of claims 1 to 5,
The information recording medium discriminating apparatus characterized in that the emitting means emits the light beam used first after discriminating the type last in discriminating the type . An emission process of emitting a plurality of light beams having different wavelengths from each other;
A light receiving step of receiving reflected light from the information recording medium of each of the emitted light beams, and outputting a received light signal corresponding to the received reflected light, respectively;
Either one of a tracking error signal group including a tracking error signal corresponding to each of the light beams or an RF signal group including an RF signal corresponding to each of the light beams using each of the output light reception signals. A generating step for generating a signal group of
CD-R, CD-RW, DVD (S), DVD (D), DVD-R, or D based only on the amplitude ratio of signals included in one of the signal groups corresponding to each of the light beams. A determination step of determining the type of the information recording medium which is one of VD-RW;
Including an information recording medium . In the information recording medium discrimination method according to claim 7,
In the emitting hand step, a first light beam and a second light beam having different wavelengths are emitted, respectively.
In the light receiving step, the reflected light of the first light beam from the information recording medium is received and a first received light signal is output, and the reflected light of the second light beam from the information recording medium is received. To output the second received light signal,
In the generating step, a tracking error signal corresponding to the first light reception signal and a tracking error signal group corresponding to the second light reception signal, or an RF signal corresponding to the first light reception signal and the second light reception. Generating one of the RF signal groups including the RF signal corresponding to the signal,
Furthermore, in the discrimination step, the type of the information recording medium is discriminated based only on the amplitude ratio of signals included in any one of the signal groups .

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